Fixed threshold validation.

ih/conf.py

@@ -745,6 +745,9 @@ valid = {
             },
             "--findSeed": {
                 "type": "exist"
+            },
+            "--binary": {
+                "type": "exist"
             }
         }
     },
@@ -1202,7 +1205,9 @@ valid = {
                 "value": ""
             },
             "--thresh": {
-                "type": "numeric"
+                "type": "string",
+                "validation": "list",
+                "value": ["binary", "inverse", "truncate", "tozero", "otsu"]
             },
             "--max": {
                 "type": "numeric",

ih/imgproc.py

@@ -555,7 +555,7 @@ class Image(object):
         Thresholds the image based on the given type.  The image must be
         grayscale to be thresholded.  If the image is of type 'bgr' it is
         automatically converted to grayscale before thresholding.
-        Supported types are: binary, truncate, tozero, and otsu.
+        Supported types are: binary, inverse, truncate, tozero, and otsu.
         """
         if self._isColor():
             self.convertColor("bgr", "gray")

scripts/ih-threshold

@@ -7,7 +7,7 @@ parser = argparse.ArgumentParser(description = "Converts an image between color
 parser.add_argument("--input", dest="input", help="Path to input image.", required = True)
 parser.add_argument("--thresh", dest="thresh", default=127, type=int, help="Threshold cutoff value.")
 parser.add_argument("--max", dest="max", default=255, type=int, help="Write value for binary threhsold")
-parser.add_argument("--type", dest="type", default="binary", help="Threshold type, one of: binary, trunc, tozero, otsu.")
+parser.add_argument("--type", dest="type", default="binary", help="Threshold type, one of: binary, inverse, trunc, tozero, otsu.")
 parser.add_argument("--outputdir", dest="outputdir", default=".", help="Path to write output files, if not specified use current directory.")
 parser.add_argument("--output", dest="output", default=None, help="Name of output image to write, if not specified, use input image name.")
 parser.add_argument("--writeblank", default=False, action="store_true", help="If errors happen, write a blank file.  Used to ensure dependent files exist for pegasus workflows.")